Not sure if it’s new in iOS 7, Safari now can save your password and AutoFill saved password when needed, just like we see on the desktop version of browsers.
To see what’s been saved or use it to reveal the password you’ve forgotten, go to Settings → Safari → Password & AutoFill.
Tapping Saved Passwords, and you will be prompted to enter the passcode you have set on your device before seeing all the password it saved.
However, If you are still not comfortable having, you can turn the feature off by tapping the option “Names and Passwords“. Once it’s off, you won’t be able to save any login info for AutoFill purpose anymore.